Acute respiratory morbidity in late preterm infants

Background Late preterm (LP) infants [gestational age (GA): 3436 weeks] are at increased risk of neonatal acute respiratory morbidity compared with term infants (GA: 3741) [1,2]. The observed rate of acute respiratory morbidity, in a population of about 20,000 LP infants, was 10-12% vs 1.4% of term infants [1]. Transient tachypnea of the newborn (TTN) and respiratory distress syndrome (RDS) are the most common diagnosis, with RDS rate reaching 10.5% in infants born at 34 weeks of GA [1,2]. Major causes of respiratory morbidity in LP are: prematurity and birth by Cesarean Section (CS) [1,3]. Material and methods We retrospectively studied 830 LP and moderate preterm (MP) infants (GA: 33-36 weeks) admitted to our unit from June 2009 to December 2013. Infants were classified according to GA: 33 weeks (n = 129), 34 weeks (n = 176), 35 weeks (n = 225), 36 weeks (n = 300). Clinical charts for each patient were reviewed and main diagnosis recorded.